A method for fault diagnosis of photovoltaic group string under non-uniform irradiance

Abstract

The invention discloses a fault diagnosis method of photovoltaic group string under non-uniform irradiance, In the case of irradiance inconsistency caused by changeable weather, the environmental parameters of photovoltaic modules at different positions are measured by irradiance sensors and temperature sensors, and the photovoltaic current, voltage and output power are estimated theoretically byusing the equivalent circuit model of photovoltaic cells. At the same time, the actual photovoltaic current, voltage and output power are measured at the bus box of the photovoltaic series. Then the open-circuit fault and short-circuit fault are coded to get the theoretical output power function. Finally, taking the absolute value of the difference between the theoretical output power and the actual output power of the photovoltaic group string as the optimization objective, the objective function is optimized by using the enhanced fireworks algorithm with fast mining and exploration performance, and the fault diagnosis and location of the photovoltaic group string are realized. The invention can enable the operation and maintenance staff of the photovoltaic power station to arrange the maintenance of the photovoltaic module which is in trouble in time.

Description

technical field [0001] The invention relates to a photovoltaic string fault diagnosis method, in particular to a photovoltaic string fault diagnosis method under non-uniform irradiance. Background technique [0002] With the depletion of traditional energy sources such as fossil fuels and the increasingly prominent environmental pollution problems, human needs for new energy sources are becoming more and more urgent. Solar energy has the advantages of cleanness, environmental protection, safety, reliability, and sustainable development, and is an ideal renewable new energy source. At present, photovoltaic power generation is an effective technology for converting solar energy into electrical energy, which can effectively alleviate the energy crisis and improve environmental pollution problems. As an important part of the photovoltaic power generation system, the photovoltaic array can theoretically have an average lifespan of 20 to 30 years. Problems such as circuit failur...

AI Technical Summary

Problems solved by technology

On-line detection generally includes photovoltaic array fault detection methods based on mathematical models and intelligent photovoltaic array fault diagnosis systems. The shortcomings of low diagnostic accuracy and high fault false alarm rate have increased the work intensity of on-site operation and maintenance personnel, and even serious fault false alarms have occurred, directly affecting the efficiency, safety and stability of photovoltaic power generation systems

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